Rock-drill chuck.



F. FRANZ, W. S. TOWER & A. H. WELLS.

ROCK DRILL CHUCK.

APPLICATION FILED DEG. 9, 1912.

Ilg Patented Dee. 16, 1.913.

2 SHEETS-SHEET l.

D ff r i 1% 1. if [1% a 2 F. FRANZ, W. S. TOWER & A. H. WELLS. ROCK DRILL CHUCK.

APPLICATION FILED DEG4 9, 1912.

LOSL Patented Dec. 16, 1913.

2 SHEETS-SHEET 2.

INVE/I/TURS ci Afm/mms 74 @Wm/MM@ lNlllFED STATES PATENT @FFllCllzo FRANK FRANZ, WALTER S. TOWER, AND ARCHIBALD H. WELLS, OF WALLACE, IDAHO.

ROCK-DRILL CHUCK.

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Specication of Letters Patent. Patented De@ 16, HMLS.,

Application filed December 9, 1912. Serial No. 785,787.

Y 1o all whom t may Concern Be it known that we, FRANK FRANZ, Umain S. TOWER, and ARCHIBALD H. lViiLLs, all residing at l/Vallace, in the county of Shoshone and State of Idaho, have invented certain 'new and useful Improvements in Rock-Drill Chucks, of which the following is a specication.

@ur invention has reference to chucks for reciprocating rock drills and it primarily has for its object to provide a simple, economically and compactly made, and strong device for clamping the bit in rigid connection with the reciprocating member of the drilling apparatus, and in which the parts are especially designed so that they automatically become self tightening under the impact force of the bit as it is hammered into the surface to be drilled.

Another and important object of our invention is to provide an improved means for clamping the bit which includes a special construct-ion of gib engaging key and the coengaging parts whereby the key while operating under the impacting blows of the drill to effect a positive clamping of the bit, remains in such position, relatively t0 the bit and the housing in which the bit clamping means is carried, that it can be quickly loosened by a very slight tap on the end thereof and which under continued drilling operation does not become battered or1 deformed.

lith other objects in View that will be hereinafter apparent, our invention consists in a rock drill chuck embodying the peculiar construction and novel arrangement of parts, hereinafter fully explained, specifically pointed out in the appended claims and,

illustrated in the accompanying drawings, in which:

Figure 1 is a perspective. view of a drill chuck embodying our invention. 'Fig 2 is a vertical longitudinal section of the same, parts being inside elevation and shown in their operative or bit clamping. position. Fig. 3 is a transverse section thereof on the line 3 3 on Fig. 2. Fig. 4 is a longitudinal section of the same, the parts being shown shifted yto illustrate the manner of assembling the same for use. Fig. 5 is a detail perspective View of the bearing or housing end of the sleeve, the housing being shown as a separate member. Fig. 6 is a perspective view of the gib, the key, the sleeve and the bit socket members separated; Fig. 7 is a detail view of a slightly modified forin of the sleeve or housing hereinafter referred to.

In the drawing, is shown a practical embodiment of our invention, and the same includes a member 1, provided with a stop collar 10, and which forms a part of the reciprocating plunger of the drill mechanism. The outer end of member 1 has a long socket 2 containing the bushing 3 in which is received the drill bit el, the said bushing and the socketed end of the member 1 having alining elongated and longitudinally extending slots 5 6 that receive the gib '7 whose upper edge is concaved to snugly engage the bit shank, and whoseupper end is rearwardly inclined, as shown.

8 designates a sleeve that is slidably mounted upon the member 1 and it is held for a limited movement on the said member 1 by the shoulder 10. Sleeve 8 has a radial extension 81 formed with a wedge shaped longitudinal slot or housingSQ, the top or clamping surface of which inclinesA rearwardly. The lower part of the sleeve 8 is made thicker than its sides whereby to in-V crease the weight of the said lower part of the sleeve to off-set the weight of the keys, spring housing, and the main housing S2, and thereby balance the weight of the piston, relatively to its axis, and in consequence .help the ratcheting motion of the piston when at work.

9 designatesy a supplement housing mounted on the inner or rear edge of the eX- tension 81 and the said housing may be a` separate member and secured to the said eX- tension S1 by means of lugs 91 on the said housing adapted for lapping over the eXtensioii S1 and for engaging seats 83 in the housing in which they are held by screws 12. Instead of the housing being an attached part of the extension 81, it may be formed integral, as shown in Fig.Y 7.

11 designates what we term the gib key, which, in practice, is a short tapering or wedge shaped bar, the upper facel 20 of which is rounded to engage the correspondingly round-clamping face 21 of the housing 82. 1t should be here stated that the taper of the gib key 11 is on the upper face and the said taper or incline and the co-engaging incline or taper surface of the housing are of different planes, the taper of the key 11 in the practical arrangement of our invention being one and seven-eighths of an inch to the foot while the face 21 of the sleeve is tapered one and one-half inches per foot. By reason of the difference in the taper of the wedge faces of the housin surface 21 and the key surface 20, the latter, when placed on top of the gib 7 as shown, makes up the required taper in the Wedge shaped slot, of one. and one-half inches per foot, that is to say, both keys, the gib 7 and the key member 11, when placed together, make pp a taper of one and one-half inches to the oot.

15 designates va stout coil spring that is supported within the housing 97 oner end of which is mounted upon a boss or rivet 16, formed on the housing, and the other end seats in a socket 17 in the adjacent end of the key 11. The key 11 has lateral extensions 12-13, at its opposite ends, the extensions 13 serving the purpose of keeping the tension on the spring 15 and also for preventing the key going too far forward, whereas the extensions 12011 the other or smaller end of the key serve to protect the spring 15 from too much recoil when the key 11 is driven back by tapping the outer end thereof, as the said extensions, should the key be struck with excess force will engage the front face of the housing.

By reason of the peculiar construction and combination of parts as describedl and shown the key is always held up to its operative or wedging position by the spring 15 and fur: ther by reason of such positioning of the key when the sleeve 8 is impelled forwardly by the force of the drill striking the rock, the wedge of the key 11 between the sleeve and'the gib is uniform and such that the gib is positively forced down to the desired creeping action with respect to the drill.

From the foregoing taken in connection with the drawing, it is believed that the complete construction, the manner of its use and the advantages of our invention will be readily understood by those skilled in the art.

What we claim is:-

'1. A drill chuck comprising a bit receiving body having a longitudinal slot in the bit holding end, a bit engaging gib having a rearwardly inclined upper Wedging face, a sleeve slidable upon the bit holding body, and including a socket portion having an inclined Wedging face that inclines in the same direction as the wedge face of the gib, a Wedge key that tapers from the inner toward the outer end adapted for fitting in the vsocket for engaging the gib and the wedge face of the socket.

2..A drill chuck comprising a bit receiving body having a longitudinal slot in the bit holding end, a bit engaging gib held in the said slot, the said gib having arearwardly inclined upper face, a sleeve slidable on the bit holding body 'and including a main socket portion having an inclined bearing surface, a key having the cross sectional shape of the space between the inclined faces of the sleeve and the gib, the said key being endwise inscrtiblc in the said space for engaging the inclined surfaces of the gib and the sleeve bearing surfaces, a socket member mounted on said sleeve and in communicatio-n with the wedge space of the same, and a spring held within said socket member and engaging said key at its inner end to continuously tend to push said key to its Wedgving position, said key having a recess to receive the end of said spring.

FRANK FRANZ. WALTER S. TOWER. ARCHIBALD H. WELLS. Witnesses AUGUST MARSHALL, NORMAN EBBLEY. 

